1. Field of the Invention
The present invention relates to a work vehicle, in particular an agricultural or construction tractor, with a cab disposed in the area above the rear axle, whose lower portion lies partially between the rear wheels and covers at least part of the power train.
2. Description of the Related Art
It is of great importance to have good access to the power train components, the brake system and other mechanical, electrical and hydraulic mechanisms beneath the cab to perform maintenance, repairs and cleaning. Access from above is hampered by the cab. Access from the side can be obstructed by the parts of the frame or the like. Access from below is rather difficult and not adequate for much of the work to be done. It is also unsatisfactory if a crane has to be used to obtain access to the components.
In the case of tractors, access to the components beneath the cab traditionally has been gained by removing the cab from the chassis (as used herein, "chassis" should be understood to mean all of the vehicle except the cab). To do this, all connections between the cab and the chassis must first be undone. This includes all the screws fastening the cab to the chassis, as well as all electrical cables, Bowden cables, hydraulic lines and the like through which steering and other signals can be exchanged between the cab and the rest of the vehicle. Undoing these connections frequently requires special tools. Once the connections are undone, the cab must be lifted off of the chassis, for example, with a crane. Typically, a crane hook is hooked into an eye hook fastened to the cab roof frame to do this.
Removing and later replacing the cab is very time-consuming and can occupy two work days. Furthermore, this work is only possible where a crane is available. This is usually true only of relatively large shops with high ceilings.
One way of obtaining access without removing the cab entirely would be to tilt the cab. The broad principle of tilting the cab is known in the art. For example, the cabs in many trucks can be tilted to the front. However, tilting of the cab to the front is not possible, or possible only to a limited extent, on many work vehicles, such as, for example, agricultural or construction tractors with a cab mounted over the rear wheels.
A work vehicle with a laterally tiltable cab is known in the art from DE-OS 28 41 575. In this case, the cab is disposed over the engine in the area of the relatively small front wheels. The cab floor lies above the upper edge of the wheels, so that the wheels are not a hindrance during tilting. A lifting apparatus between part of the vehicle frame and the cab, for example, a scissor jack, is provided for tilting.
This laterally tiltable cab cannot be used with more conventional work vehicles where the cab is between the rear wheels, since the rear wheels would interfere with tilting of the cab and prevent sufficient lateral tilt to obtain access to the components under the cab. In addition, even in the prior art front mounted cab, the tilt angle is relatively small. This is justifiable there since tilting to both sides is possible and the tilting is intended for maintenance but not, for example, for the exchange of transmission units.
Tilting of the cab is treated in relatively nonspecific terms in DE-OS 28 41 575. For example, it is not mentioned how the connecting elements between the controls in the cab and units disposed on the chassis of the vehicle are to be dealt with.